That is only the combustion of a hydrocarbon. Rust is a combustion reaction because oxygen is added.
Fe(s) + O2(g) => FeO2(s)
1) Well, you need to logically think about which of the pecan trees would be better. Tree 3 may have more clusters but they taste bitter so this is out of the option. So Tree 4 and Tree 1 would be best because they both have rich and buttery tastes and they both have a lot of clusters.
2) Not quite sure about this one, sorry :(
Answer: This is known as substitution cipher.
Explanation:
